Mitral valve rotator assembly

ABSTRACT

A valve rotator comprising a body having a generally annular peripheral surface at one end of the body and a central cavity opening at such end. The annular peripheral surface substantially surrounds the central cavity and has an interlocking surface region configured to interlock with a rotor of a rotatable valve. The body had a generally annular shoulder adjacent such one end which generally faces such end of the body. The annular peripheral surface extends toward that end of the body from the annular shoulder.

This is a continuation, of application Ser. No. 07/157,037, filed Feb.16, 1988, now abandoned.

BACKGROUND OF THE INVENTION

As is well known, prosthetic heart valves are used as replacements fordiseased natural heart valves. Generally, prosthetic heart valves aredivided into two classes, i.e. mechanical valves and tissue valves. Oneform of mechanical valve employs two leaflets or, more broadly, valveelements, which pivot between open and closed positions. One problemwith valves of this type is that the pivotal movement of the valveelements can be impeded by tissue near the orifice in which the valve isimplanted.

One way to solve this problem is to employ a rotatable heart valve. Arotatable heart valve includes a frame attachable to tissue around theorifice, a rotor mounted on the frame for rotation and one or more valveelements carried by the rotor and movable with respect to the rotor toopen and close the heart valve. The frame includes a suture ring, and toimplant a valve of this type, the surgeon sutures the suture ring in thedesired position within the heart. Next, the valve elements aremanipulated to ascertain if their movement is impeded in any way. Ifmovement of the valve elements is impeded, the surgeon rotates the rotorwith respect to the frame to a new angular position in which theadjacent tissue does not impede the pivotal movement of the valveelements.

This technique is very satisfactory in reducing the likelihood thattissue will impede the pivotal movement of the valve elements. However,some difficulty has been encountered with the implement used to rotatethe rotatable valve. For example, the implement disclosed in Martin U.S.Pat. No. 4,683,883 is designed to function as both a valve holder andvalve rotator. Although satisfactory for some purposes, it has beenfound that it is not as easy as desired to drivingly engage the rotatorwith the rotatable valve particularly when the surgeon is working inregions not readily visible or at difficult angles. Furthermore, oncethe rotator does drivingly engage the heart valve, it is not as easy asdesired to maintain this engagement during rotation of the valve. Thesefactors are significant because it is important that the valve berotated quickly and accurately to minimize the time required for thisportion of the surgery and to assure accurate rotational positioning ofthe valve. In addition, in order to maintain the engagement desired,additional force may be applied to the rotator and hence to the heartvalve, and this is also undesirable. Finally, some prior art valverotators interfere with the pivotal movement of the valve elements, andthis is undesirable because it inhibits the testing of the valveelements to assure that they can move freely between the closed andfully opened positions.

SUMMARY OF THE INVENTION

This invention provides a heart valve rotator which generally overcomesthe disadvantages noted above. The rotator of this invention can beeasily drivingly coupled to the rotatable valve and the drivingengagement is easy to maintain with a minimum of force applied to theheart valve. Also, the valve rotator of this invention does not impedethe free pivotal movement of the valve elements between the closed andfully open positions. Although this invention is particularly adaptedfor a mitral valve, it is also applicable to rotatable heart valves ingeneral.

This invention can advantageously be embodied in a valve rotator whichincludes a body having a generally annular peripheral surface at one endof the body and a central cavity opening at such one end. The annularperipheral surface substantially surrounds the central cavity and facesoutwardly. The annular peripheral surface has an interlocking surfaceregion configured to interlock with a rotor of a rotatable valve. Thebody has a generally annular shoulder adjacent and generally facing suchone end of the body. The annular peripheral surface extends toward suchone end of the body from the annular shoulder.

Several factors contribute to the ease of drivingly coupling the valverotator to the heart valve. For example, preferably, although notnecessarily, the interlocking surface region includes a plurality ofpairs of flat surfaces. By providing a plurality of pairs of flatsurfaces, obtaining driving engagement is made much easier because lessrelative rotation between the rotator and heart valve is needed toobtain driving engagement.

Preferably, although not necessarily, the end of the body inserted intothe heart valve is annular. This annular end of the body rides on theheart valve prior to driving engagement of the interlocking surfaceregion of the body and the heart valve. Because this end is annular, itcan more stably support the rotator than if one or more long lengths ofthis annular surface were removed.

Various features contribute to keeping the valve rotator drivinglycoupled to the heart valve. For example, the annular peripheral surfaceand the annular shoulder stably support the rotator against rockingmotion when the rotator is drivingly coupled to the heart valve. Inaddition, this enables the rotator and heart valve to stay engaged withless axial force applied to the heart valve.

To the extent that the pairs of flat surfaces are increased, obtainingdriving engagement with the heart valve is made easier as describedabove. However, the flat surfaces, which are not in driving engagementwith corresponding flat surfaces of the heart valve, are spaced from theheart valve where they are less able to offer stability to the drivingconnection between the rotator and the heart valve. However, thisinvention utilizes intermediate arcuate surfaces for spacing the flatsurfaces circumferentially, and these intermediate arcuate surfaces arein continuous sliding engagement with the heart valve when the rotor isdrivingly coupled to the heart valve. Preferably, the intermediatearcuate surface are contiguous adjacent flat surfaces so that the entirecircumferential length of the annular surface is utilized either tofacilitate initial driving engagement or to maintain such drivingengagement.

A region of the body is insertable into the heart valve and the cavityis sized and positioned to prevent this region of the body frominterfering with the free pivotal movement of the valve elements. Inaddition, means is provided for limiting the depth of insertion of thisregion of the body into the heart valve. This limiting means and thecavity prevent the body from interfering with movement of the valveelement.

The cavity in the body can be arranged so that a portion of the valveelement extends into the cavity in at least one position of the valveelement. In a preferred construction, the heart valve includes a valveseat and the valve element is engageable with the valve seat to closethe heart valve. The limiting means prevents such region of the bodyfrom extending into the heart valve all the way to the valve seat. Theannular wall can have a variety of different shapes in radial crosssection, such as cylindrical with one or more flats to form theinterlocking surface region, polygonal, etc. Although the annular wallmay have some interruptions, it should not have interruptions ofsufficiently great circumferential length so as to material diminish thefirm seating engagement which a continuous annular wall would provide.Thus, in a preferred construction, the annular wall extends continuouslyaround the cavity.

In a preferred construction, the body has an annular wall and theannular peripheral surface is on the annular wall. In this preferredconstruction, the cavity is at least partially defined by the annularwall.

The valve rotator can be manually rotated, and for this purpose, it ispreferred to provide means at the other end of the body for facilitatingmanual gripping and rotating of the body. In addition, means is alsoprovided at the other end of the body for attaching a handle to thebody. The body can be simply and inexpensively manufactured by moldingit from a suitable rigid plastic material.

The invention, together with additional features and advantages thereof,may best be understood by reference to the following description takenin connection with the accompanying illustrative drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of one preferred form of heart valve rotatorconstructed in accordance with the teachings of this invention.

FIG. 2 is a side elevational view of a rotator which includes a handle.

FIG. 3 is a fragmentary elevational view partially in section showingthe rotator and a rotatable heart valve.

FIG. 3A is an enlarged fragmentary sectional view of a portion of FIG.3.

FIG. 4 is a sectional view taken generally along line 4--4 of FIG. 3.

FIG. 5 is a sectional view similar to FIG. 4 with the rotor of the heartvalve rotated by the rotator and with the valve elements closed.

FIG. 6 is an isometric view of a second form of heart valve rotatorconstructed in accordance with the teachings of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 2 shows a heart valve rotator 11 which comprises a body 13 and anoptional handle 15. The body 13 is preferably integrally molded of asuitable rigid plastic material.

In this embodiment, the body 13 includes a coupling section 17 and agenerally frusto-conical skirt 19. The coupling section 17 has means forfacilitating manually gripping and rotating of the body 13, and in thisembodiment, such means is in the form of a plurality of flat surfaces21. Six of the flat surfaces 21 are illustrated, and the couplingsection 17 is hexagonal, but this is purely illustrative. The couplingsection 17 also has an internally threaded axial bore 23 (FIG. 2)extending completely through it. The threads cooperate with matingthreads of the handle 15 to releasably attach the handle to the body 13.The coupling section 17 also defines a proximal end 25 of the body.

The handle 15 is an elongated metal handle with a thin bendable section26 and a knurled grasping section 28. The handle 15 may be conventionaland of the type used with a heart valve holder to insert the heart valveinto the heart for implantation.

The skirt 19 defines an annular distal end 27 of the body 13 andcooperates with the coupling section 17 to define a central cavity 29which opens at the distal end. In this embodiment, the distal end 27 isa planar surface which lies in a radial plane and which is continuousand uninterrupted.

The skirt 19 has an annular shoulder 31 (FIG. 3A) adjacent the distalend 27. The annular shoulder 31 is a planar surface and lies in a radialplane so that it faces the distal end 27. A distal region of the skirt19 forms an annular wall 33, which partially defines the cavity 29 andwhich extends from the annular shoulder 31 to the distal end 29. Theannular wall 33 has an annular peripheral surface 35 which facesradially outwardly and which has an interlocking surface region in theform of a plurality of pairs of flat surfaces 37 (FIG. 4). Although fourpairs of diametrically opposed flat surfaces 37 are illustrated, this ispurely illustrative. Adjacent flat surfaces 37 are spacedcircumferentially by intermediate arcuate surfaces 38 which arecontiguous the flat surfaces.

The annular wall 33 extends continuously and without interruption aroundthe cavity 29. As best seen in FIG. 4, the annular wall 33 has an innersurface 39 which is circular in radial cross section and which isslightly conical. The annular peripheral surface 35 is generallycylindrical except for the presence of the flat surfaces 37.

The rotator 11 is particularly adapted for use with a rotatable heartvalve, such as rotatable mitral heart valve 41. The heart valve 41,which may be of conventional construction, comprises an annular frame43, an annular rotor 45 and a pair of valve leaflets or valve elements47 pivotally attached to the rotor 45 in a conventional manner, such asby mounting balls 49 carried by the valve elements and pivotallyreceived in the rotor 45. The frame 43 can be of any conventionalconstruction for a rotatable heart valve, and as such, may include asuture ring 51 and a relatively rigid mounting ring 53. The rotor 45 maycomprise, for example, a housing 55 of annular construction and astiffener ring 57 surrounding the housing and fixedly attached thereto.The stiffener ring 57 is receivable in a corresponding annular groove inthe mounting ring 53 to mount the rotor 45 for rotation relative to theframe 43. Rotational movement of the rotor, relative to the frame 43 isretarded by frictional forces which are sufficient to retain the rotorin whatever angular position it is placed. The housing has an upper endor flat annular shoulder 54 lying in a radial plane and an innergenerally circular surface 56 as viewed in cross section (FIG. 4) withone pair of diametrally opposed flat driven surfaces 58.

The rotor 45 has an opening 59 extending therethrough in which the valveelements 47 are pivotally mounted. The valve elements can be pivotedbetween a closed position illustrated by the right-hand valve elements47 in FIG. 3 and an open position illustrated by the left-hand valveelement in FIG. 3. Of course, in actual use, the valve elements 47 willopen and close together and the position of the valve elements 47 inFIG. 3 is for illustrative purposes only. The housing 55 has an annularvalve seat 61 which is engaged by the periphery of the valve elements 47in the closed position of the valve 41. The heart valve 41 illustratedand described herein is commercially available from Baxter of Irvine,Calif., and for that reason, is not described in greater detail herein.

In open-heart surgery, the diseased natural valve is removed and theprosthetic heart valve 41 is implanted by suturing the suture ring 51 totissue 63 surrounding the orifice 65 in which the heart valve 41 isplaced. This is accomplished according to conventional techniques withthe surgeon roughly angularly orienting the heart valve 41 to achievethe approximate desired angular orientation of the valve elements 47about the axis of the orifice 65 before the heart valve 41 is sutured inplace. After the suture ring 51 is sutured to the tissue 63, the surgeonmanipulates the valve elements 47 between the closed and fully openpositions to ascertain if any of the tissue 63 adjacent the valve isimpeding the free pivotal movement of the valve element. If suchimpediment exists, the surgeon rotates the rotor 45 and the valveleaflets 47 to a new angular position in which there is no impediment tothe free pivotal movement of the valve element.

To accomplish this, the surgeon inserts the annular wall 33 into theopening defined by the inner surface 56 of the housing 55 of the rotor45. This insertion process is facilitated by the presence of multiplepairs of the flat surfaces 37. Accordingly, regardless of the angularposition of the rotator 11 when it first contacts the shoulder 54 of thehousing 55, only a relatively small amount of rotation of the rotator isnecessary to align one pair of the flat surfaces 37 with the flat drivensurfaces 58 of the housing 55 of the rotor 45. In addition, this shortdegree of rotation can be more stably carried out because the distal end27 is a continuous, flat annular surface which is better able to supportthe rotator on the shoulder 54 during this rotational movement.

Once the annular wall 33 is received within the housing 55 as shown inFIGS. 3 and 3A and driving engagement between the flat surfaces 37 and58 is achieved, it is relatively easy to keep the valve rotator 11drivingly coupled to the rotor 45. In this regard, the annularperipheral surface 35 provides firm seating engagement with the innersurface 56 of the frame 55 to stably support the rotator against rockingmotion. This also enables the rotator 11 and the rotor 45 to staydrivingly engaged with less axial force applied to the heart valve 41.The rotator 11 can be manipulated and rotated by grasping the flatsurfaces 21 or by using the handle 15.

Although the flat surfaces 37, which are not drivingly engaged with thedriven surfaces 58 are not in continuous contact with the inner surface56, the intermediate surfaces 38 provide such continuous contact and thenon-engaged flat surfaces 37 are closely adjacent the inner surface 56.Accordingly, this arrangement of multiple sets of flat surfaces 37 andintermediate surfaces 38 provides for a desired combination ofestablishing driving engagement and for maintaining such drivingengagement.

With the rotator 11 seated in the rotor 45 as shown, the shoulders 31and 54 engage to limit the depth of insertion of the annular wall 33 andthe distal end 27 into the rotor 45. Specifically, the distal end 27does not extend to the valve seat 61 where it could interfere withcomplete movement of the valve elements 47 to the closed position.

Also, the cavity 29 helps prevent the body 13 from interfering withmovement of the valve elements 47 with respect to the rotor 45. In thisregard, the cavity 29 provides space into which portions of the valveelements 47 can extend as shown in FIG. 3.

FIG. 6 shows a heart valve rotator 11a which is identical to the heartvalve rotator 11 in all respects not shown or described herein. Portionsof the heart valve rotator 11a corresponding to portions of the heartvalve rotator 11 are designated by corresponding reference numeralsfollowed by the letter a.

The coupling section 17a differs from the coupling section 17 in that ithas an annular knurled region 71 in lieu of the flat surfaces 21 tofacilitate manual gripping. In addition, the coupling section 17a isgenerally cylindrical and does not have means for attaching of thehandle 15.

The rotator 11 has a solid plastic stem 73 of reduced diameter whichjoins the coupling section 17a to a generally dome-shaped head 75. Thecavity 29a is relatively shallow and is formed in the head 75. Thus, therotator 11a effectively eliminates the skirt 19 in favor of the stem 73and the head 75 and any skirt in the rotator 11a is quite short andlimited to the depth of the cavity 29a.

Although exemplary embodiments of the invention have been shown anddescribed, many changes, modifications and substitutions may be made byone having ordinary skill in the art without necessarily departing fromthe spirit and scope of this invention.

We claim:
 1. A valve rotator adapted to be used for engaging androtating a heart valve rotor which is rotatably mounted in a frame thatis formed for suturing to tissue, the heart valve rotor including one ormore valve leaflets and a surface having a plurality of regions, thevalve rotator comprising:a body having a first portion extending outfrom the body, the body first portion comprising a distal end and anannular wall extending from the distal end of the first portion, theannular wall having a plurality of regions that include at least threeouter flat surfaces alternating with at least three arcuate outersurfaces, the plurality of regions of the body first portion adapted tobe adjacent the heart valve rotor surface and the plurality of regionsof the heart valve rotor surface including complementary inner surfacesconfigured to releasably abut the outer surfaces of the annular wallwhen the complementary surfaces are brought into alignment by rotationof the body, the complementary surfaces being configured to bear againsteach other when the body is further rotated, whereby rotation of thebody rotates the rotor; and means for rotating the body.
 2. The valverotator of claim 1 wherein the heart valve rotor has an opening, thebody being further formed to allow for essentially free movement of thevalve leaflets when the body first portion is received by the rotoropening.
 3. The valve rotator of claim 2 wherein the complementarysurfaces of the plurality of regions of the heart valve rotor are flatsurfaces which are spatially separated to allow for individual alignmentwith respective ones of the flat surfaces of the annular wall.
 4. Thevalve rotator of claim 1 wherein the complementary surfaces are shapedto allow the body first portion and the heart valve rotor to bedisengaged by sliding the body first portion outward from the heartvalve rotor.
 5. The valve rotator of claim 1 wherein the body furtherincludes an annular shoulder which extends radially out from the body ata location adjacent to the annular wall, and the heart valve rotorfurther comprises a housing having a shoulder, wherein the body annularshoulder is dimensioned and shaped to engage the shoulder of the heartvalve rotor when the annular wall is received in the rotor to limitfurther movement of the annular wall.
 6. The valve rotator of claim 1wherein the rotating means is a handle coupled to the body.
 7. The valverotator of claim 1 wherein the complementary surfaces of the body firstportion and the heart valve rotor ensure for disengagement between thebody first portion and the heart valve rotor with essentially nomovement of the heart valve rotor.
 8. An assembly comprising:a rotatableheart valve comprising a heart valve rotor and a frame which is formedfor suturing to tissue, the heart valve rotor rotatably mounted in theframe and including one or more valve leaflets and a surface having aplurality of regions; and a valve rotator comprising:(a) a body having afirst portion extending out from the body, the body first portioncomprising a distal end and an annular wall extending from the distalend of the first portion, the annular wall having a plurality of regionsthat include at least three outer flat surfaces alternating with atleast three arcuate outer surfaces, the plurality of regions of the bodyfirst portion adjacent the heart valve rotor surface and the pluralityof regions of the heart valve rotor surface being configured withcomplementary inner surfaces which releasably abut the outer surfaces ofthe annular wall when the complementary surfaces are brought intoalignment by rotation of the body, which complementary surfaces bearagainst each other when the body is further rotated, whereby rotation ofthe body rotates the rotor; and (b) means for rotating the body.
 9. Theassembly of claim 8 wherein the heart valve rotor has an opening, thebody being further formed to allow for essentially free movement of thevalve leaflets when the body first portion is received by the rotoropening.
 10. The assembly of claim 9 wherein the complementary surfacesof the plurality of regions of the heart valve rotor are flat surfaceswhich are spatially separated to allow for individual alignment withrespective ones of the flat surfaces of the annular wall.
 11. Theassembly of claim 8 wherein the complementary surfaces are shaped toallow the body first portion and the heart valve rotor to be disengagedby sliding the body first portion outward from the heart valve rotor.12. The assembly of claim 8 wherein the body further includes an annularshoulder which extends radially out from the body at a location adjacentto the annular wall, and the heart valve rotor further comprises ahousing having a shoulder, wherein the body annular shoulder isdimensioned and shaped to engage the shoulder of the heart valve rotorwhen the annular wall is received in the rotor to limit further movementof the annular wall.
 13. The assembly of claim 8 wherein the rotatingmeans is a handle which is coupled to the body.
 14. The assembly ofclaim 8 wherein the complementary surfaces of the body first portion andthe heart valve rotor ensure for disengagement between the body firstportion and the heart valve rotor with essentially no movement of theheart valve rotor.